1. Technical Field
The present disclosure relates to the field of safety needles having retraction structure. More particularly, the present disclosure relates to safety needles incorporating lockout mechanisms to prevent re-advancement of an associated needle after initial use and retraction
2. Background of Related Art
Hypodermic needles are used for venous access in a variety of medical procedures requiring fluid sampling, percutaneous medication injection, or other delivery to or withdrawal of fluid from a patient. Various intravenous needle assemblies are known which can generally include blood collection needles, infusion needles, hemodialysis needles, needles associated with blood collection bags, etc. Problems associated with the use of intravenous needles may include needle stick injury, stabilization of the needle on a patient, and ease of insertion and withdrawal of the needle from the patient.
Some of the health risks associated with hazardous needle exposure include HIV, hepatitis, and other blood-borne pathogens. Medical professionals are in danger of contracting such blood-borne pathogens from infected patients by inadvertent needle sticks from needles contaminated during medical, dental, laboratory etc. procedures.
Various protective devices including sheaths, have been used to shield sharp tips of needles in order to alleviate danger of needle stick injury to a user. Additionally, many needle devices include the provision of an automatic retraction system to shield the needle within a housing associated with the needle assembly after use. Examples of devices including spring-loaded retraction mechanisms which have no provision for preventing inadvertent, premature retraction include U.S. Pat. No. 5,423,758 to Shaw, U.S. Pat. No. 5,779,679 to Shaw, U.S. Pat. No. 6,096,005 to Botich, U.S. Pat. No. 6,179,812 B1 to Botich and U.S. Pat. No. 6,210,371 B1 to Shaw.
Unfortunately, the same automatic retraction system that is designed to protect the user from needle stick injury may inadvertently be reversed to re-extend the needle from a housing and thereby still pose a threat of needle stick injury. Furthermore, in many systems, an entire needle system is movable within an outer housing and is retracted due to the action of the spring between the outer housing and the needle system. It is possible that a user could accidentally grasp the outer housing and push against the bias of the spring to re-extend the needle.
Therefore, it would be desirable to provide a safety needle which includes a blocking or lockout structure to prevent re-advancement of a needle through and out of the needle housing after the needle has been used and the retraction system activated. It would be further be desirable to provide a lockout structure which is simple, low-cost, and can be easily manufactured on existing safety needle components.